2. ABSTRACT Older African American (AA) women have the highest prevalence of both obesity and frailty. In academic, expert- led interventions, obese, frail, older individuals both lost weight and improved their physical function. However, because of high personnel costs and nonexistent nationwide infrastructure, large-scale implementation of these interventions is impractical. The long-term goals are to eliminate the health disparities of obesity and frailty in older AA women. This proposal?s overall objective is to determine the effects of a low-cost, community-based, peer-led weight loss program with a national infrastructure on obesity, physical function, and healthcare utilization in older AA women. To treat obesity and frailty in older AA women, it is critical to test a weight loss intervention that 1) has preliminary evidence of benefit; 2) is acceptable to older AA women; 3) is affordable; and 4) can be broadly disseminated. Take Off Pounds Sensibly (TOPS) is a national, nonprofit, community-based, peer-led weight loss program that meets these criteria. First, the applicant?s retrospective database analyses of TOPS showed two important results: 1) Participants who renew their annual membership lose and maintain significant weight loss (SWL) for up to 7 years; and 2) Compared to their younger counterparts, older women are more likely to achieve SWL. Second, the applicant started three TOPS chapters for older AA women in a successful pilot study. Though the study ended in 2012, one of the chapters is still active almost 6 years later. Third, TOPS is affordable; it only costs $92 annually. Finally, TOPS has a nationwide infrastructure with chapters in all 50 states. Since obese, frail, older individuals in academic, expert-led weight loss interventions can improve their physical function, the central hypothesis is that a low cost, community-based, peer-led weight loss program with a national infrastructure can provide SWL, improved physical function, and lower healthcare utilization for AA women, an underserved, vulnerable population. The rationale for the proposed research is that TOPS and academic, expert-led weight loss interventions share components critical to successful weight loss; therefore, TOPS can deliver similar outcomes. The central hypothesis will be tested by pursuing the following aims in obese, frail, older AA women: Determine the effect of TOPS on 1) weight change and cardiovascular disease risk factors; 2) physical function and quality of life; and 3) healthcare utilization. This project is innovative because it uses a ?community to academia? approach to treat the health disparities; our study population focuses on older AA women with decreased physical function; our outcomes focus on weight, physical function, and healthcare utilization; and our unique study settings. The proposed research is significant because determining the real- world effectiveness of the TOPS program and its impact on weight, physical function, and healthcare utilization in AA women can have a widespread impact on the older population at large. Thus, it has the potential to reduce adverse geriatric outcomes among all older individuals.